Login / Signup

Catalytic Performance and Near-Surface X-ray Characterization of Titanium Hydride Electrodes for the Electrochemical Nitrate Reduction Reaction.

Matthew J LiuJinyu GuoAdam S HoffmanJoakim Halldin StenlidMichael T TangElizabeth R CorsonKevin H StoneFrank Abild-PedersenSimon R BareWilliam A Tarpeh
Published in: Journal of the American Chemical Society (2022)
The electrochemical nitrate reduction reaction (NO 3 RR) on titanium introduces significant surface reconstruction and forms titanium hydride (TiH x , 0 < x ≤ 2). With ex situ grazing-incidence X-ray diffraction (GIXRD) and X-ray absorption spectroscopy (XAS), we demonstrated near-surface TiH 2 enrichment with increasing NO 3 RR applied potential and duration. This quantitative relationship facilitated electrochemical treatment of Ti to form TiH 2 /Ti electrodes for use in NO 3 RR, thereby decoupling hydride formation from NO 3 RR performance. A wide range of NO 3 RR activity and selectivity on TiH 2 /Ti electrodes between -0.4 and -1.0 V RHE was observed and analyzed with density functional theory (DFT) calculations on TiH 2 (111). This work underscores the importance of relating NO 3 RR performance with near-surface electrode structure to advance catalyst design and operation.
Keyphrases